title: A simplified 461-nm laser system using blue laser diodes and a hollow cathode lamp for laser cooling of Sr.
abstract: We develop a simplified light source at 461 nm for laser cooling of Sr without frequency-doubling crystals but with blue laser diodes. An anti-reflection coated blue laser diode in an external cavity (Littrow) configuration provides an output power of 40 mW at 461 nm. Another blue laser diode is used to amplify the laser power up to 110 mW by injection locking. For frequency stabilization, we demonstrate modulation-free polarization spectroscopy of Sr in a hollow cathode lamp. The simplification of the laser system achieved in this work is of great importance for the construction of transportable optical lattice clocks.
authors.affiliation: Institute of Physics, The University of Tokyo, 3-8-1 Komaba, Tokyo 153-8902, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Shimada
authors.forename: Yuko
authors.initials: Y
authors.lastname: Chida
authors.forename: Nozomi
authors.initials: N
authors.lastname: Ohtsubo
authors.forename: Takatoshi
authors.initials: T
authors.lastname: Aoki
authors.forename: Makoto
authors.initials: M
authors.lastname: Takeuchi
authors.forename: Takahiro
authors.initials: T
authors.lastname: Kuga
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Torii